# 8. Converter modules

Added in version 2.0.0.

The `MDAnalysis.converters` module contains the Converter classes that MDAnalysis uses to convert MDAnalysis structures to and from other Python packages.

If you are converting to MDAnalysis, you can use the normal syntax for creating a Universe from files. Typically MDAnalysis will recognise which library it is dealing with, so you will not need to pass in a `format` keyword.

For example:

    import MDAnalysis as mda
    from MDAnalysis import GRO
    import parmed as pmd

    pgro = pmd.load_file(GRO)  # creates parmed structure
    ugro = mda.Universe(pgro)  # you can just pass it in

If you are converting from MDAnalysis, use the `convert_to()` method. With this, you will have to specify a package name (case-insensitive).

    pgro2 = ugro.atoms.convert_to('PARMED')  # converts back to parmed structure

Another syntax is also available for tab-completion support:

    pgro2 = ugro.atoms.convert_to.parmed()

Available converters

- 8.1. ParmEd topology parser — `MDAnalysis.converters.ParmEdParser`
- 8.2. ParmEd structure I/O — `MDAnalysis.converters.ParmEd`
- 8.3. RDKit topology parser — `MDAnalysis.converters.RDKitParser`
- 8.4. RDKit molecule I/O — `MDAnalysis.converters.RDKit`
- 8.5. RDKit bond order inferring — `MDAnalysis.converters.RDKitInferring`
- 8.6. OpenMM topology parser `MDAnalysis.converters.OpenMMParser`
- 8.7. OpenMM structure I/O — `MDAnalysis.converters.OpenMM`

Converter functionalities

- 8.8. AtomGroup accessors — `MDAnalysis.core.accessors`

Developers may find the `MDAnaylsis.converters.base` module helpful for creating new converter classes.

- 8.9. Base classes — `MDAnalysis.converters.base`